ses light came on, come in to help with code

This is a discussion on ses light came on, come in to help with code within the General Help forums, part of the LSx Technical Help Section category; had the car out on saturday and the SES light came on... my reader said P0420 &quot;Catalyst System Efficiency Below ...

Agreed with above post, bad cats. I have the same code. Takes a few cycles to come back up after it's cleared too. And your o2's are getting the crap cooked out of them now too. Hurry and get those cats changed out or cut em off before you have to spend more money

Agreed with above post, bad cats. I have the same code. Takes a few cycles to come back up after it's cleared too. And your o2's are getting the crap cooked out of them now too. Hurry and get those cats changed out or cut em off before you have to spend more money

they don't do a sniffer but they hook it up to a computer and check to make sure that the O2s read something.. about the only thing that would work if i got rid of the cats would be the O2 spoofers but they are not sold anymore... they also look under the car to make sure cats are there.

yeah mine came on like a week ago.. for the samething P0420 cat. effi. below threshold.. I call gm and they told me they would have to look at it first and if it ended up being the cat. Then they would go ahead and warranty it. But if its not the cat then they would charge me for the diagnostic fee... I thought to myself thats a bunch of BS... what do you guys think..?

The cats are on recall. Call the dealer, give them your vin, schedule an appointment get it fixed for free. If the dealer needs to deviate from the manual due to aftermarket exhaust or such, expect to pay a standard 1 hour labor fee.

now i have the SLP Mass and CAI.. should i remove any of it.. or just say it came like that from the factory.. I mean SLP did do aftermarket stuff on the car when you buy from the dealer if you requested it.. any input.?

Well just came back from GM and everthing is koo they are gonna warranty the cat. So it ended up being the cat.. So to recap I had a DTC: P0420 cat effi. below thereshold bank 1.. I change the rear 02 sensor and it came back up after i cleared the code. I then switch back my old 02 and took out the new one. Went to GM and had them look at the cat. Cat is no good and they are gonna warranty it..

The cats are on recall. Call the dealer, give them your vin, schedule an appointment get it fixed for free. If the dealer needs to deviate from the manual due to aftermarket exhaust or such, expect to pay a standard 1 hour labor fee.

Is this all years of LS1's that are recalled?

My SES light just came on this morning. I haven't had a chance to get the code pulled yet though. Would a bad cat/cats cause a rough idle too?

Well just came back from GM and everthing is koo they are gonna warranty the cat. So it ended up being the cat.. So to recap I had a DTC: P0420 cat effi. below thereshold bank 1.. I change the rear 02 sensor and it came back up after i cleared the code. I then switch back my old 02 and took out the new one. Went to GM and had them look at the cat. Cat is no good and they are gonna warranty it..

Cool man, I just had my code pulled and got the same one. I guess I'll be heading to the dealer on Monday.